An electromagnetic-wave shielding sheet is an electromagnetic-wave shielding sheet used to form an electronic component-mounted substrate, the electronic component-mounted substrate including an electromagnetic-wave shielding layer covering at least a part of a step part and an exposed surface of a substrate, in which the electromagnetic-wave shielding sheet is a laminate including a cushion layer and a conductive layer, the conductive layer is an isotropic conductive layer containing a binder resin and a conductive filler, a thickness of the conductive layer is 8 to 70 μm, and a content of the conductive filler in a region on a side opposite to a cushion layer side in the conductive layer is larger than that in a region on the cushion layer side in the conductive layer.

An electromagnetic wave absorbing thermally conductive composition contains a matrix resin component, metal soft magnetic particles, and thermally conductive particles. The metal soft magnetic particles are carbonyl iron particles and are present in an amount of 30% by volume or more when the electromagnetic wave absorbing thermally conductive composition is a population parameter. A value of an imaginary part (μ″) of relative permeability of the electromagnetic wave absorbing thermally conductive composition is 0.9 or more in at least some bands in a frequency range of 18 to 26.5 GHz. The electromagnetic wave absorbing thermally conductive composition in the form of a sheet has a thermal conductivity of 2.0 W/m.Math.K or more in the thickness direction. A sheet of the present invention incudes the above composition in the form of a sheet. Thus, the present invention provides the electromagnetic wave absorbing thermally conductive composition and its sheet that can increase the value of the imaginary part (μ″) of relative permeability in a frequency band of 18 to 26.5 GHz, efficiently absorb electromagnetic wave noise in this frequency band, and also have a high thermal conductivity.

A composite shielding material in the form of syntactic foam where the spherical or spherical-like articles are encompassed by an organic or inorganic matrix material, and coated with a layer of nanostructures such as carbon nanotubes, graphene, graphene flakes. Such articles may be alternatively or additionally be covered with nano-sized metal particles and the mould is filled with organic or inorganic matrix, and micro and/or nano-sized reinforcement elements. Such material possesses both reflective and absorptive properties to improve shielding effectiveness. Also process for making the same is disclosed. The composite material can be used as an electromagnetic, thermal or acoustic shield.

Provided is an electromagnetic wave suppression sheet that contains from 400 to 600 parts by weight of a metal magnetic powder having an oxidized coating film formed on a surface thereof, from 1 to 15 parts by weight of a chelating agent, and from 1 to 10 parts by weight of an anti-aging agent, per 100 parts by weight of chlorinated polyethylene.

According to various aspects, exemplary embodiments are disclosed of thermally-conductive EMI absorbers that generally includes thermally-conductive particles, EMI absorbing particles, and silicon carbide. The silicon carbide is present in an amount sufficient to synergistically enhance thermal conductivity and/or EMI absorption. By way of example, an exemplary embodiment of a thermally-conductive EMI absorber may include silicon carbide, magnetic flakes, manganese zinc ferrite, alumina, and carbonyl iron.

An absorption device for absorbing electromagnetic radiation at least in a partial range within a frequency range from 500 MHz to 15 GHz includes a housing (1), which is at least partially transmissive to the electromagnetic radiation to be absorbed and has an inner receptacle space (3), which contains a fill, which includes irregularly arranged absorption elements (4). The absorption elements each include a carrier body (4a) made of an electrically insulating material, on which a layer (4b) is applied externally at least on one side, which is formed by an electrically conductive material.

An electrically conductive composite powder is provided for microwave shielding applications. The electrically conductive composite powder includes a core of particles formed from a material having a low density of <5 g/cm.sup.3 and a high dielectric constant of ≥10; an intermediate layer coated onto the core of particles, wherein said intermediate layer has a high electrical conductivity of >5.90×10.sup.−8 Ohm*m at 20° C.; and an outer layer that is deposited onto the intermediate layer, said outer layer comprising a material having a high oxidation and corrosion resistance of >−0.2V galvanic potential in seawater as measured via ASTM G82. The electrically conductive composite powder exhibits excellent microwave shielding performance, while also being substantially lower in cost that conventional Ag/Ni shields. The electrically conductive composite powder can be used across a broad microwave frequency range.

An electromagnetic interference (EMI) shielded device which includes an object to be shielded and an EMI shielding material encompassing the object. The EMI shielding material is made up of, but not limited to a broadband biopolymer or polymer dissolved in organic solvents and shielding guest material. The specific makeup of the shielding material and fabrication procedure of the shielding material is also included herein.

Devices, such as power tools, outdoor power equipment, lighting devices, test and measurement devices, battery packs, battery pack chargers, power supply devices, modular storage units, etc., include housing structures or other components of the devices made with graphene and/or a graphene polymeric material. The graphene polymeric materials include graphene and a polymer. The graphene polymeric materials are particularly advantageous for electromagnetic shielding purposes. Specific components of the graphene polymeric material may be selected based on their electromagnetic (“EM”) shielding effects (e.g., attenuation, reflection, and/or absorption of radiated emissions) and electrostatic discharge (“ESD”) shielding effects (e.g., dissipation of excess electrical charge and prevention of electrostatic charge accumulation).

Exemplary embodiments of the present disclosure provide a system, apparatus, and methods for producing a high-performance camouflage and thermal management composite fabric textile systems. The systems comprise woven and non-woven composite fabrics consisting of layers for thermal and electromagnetic wave propagation as well as human thermal emission control. The systems incorporate thermal plastic insulation, felt insulation, electromagnetic wave absorption materials, electromagnetic wave propagation and thermal emission control elements, and camouflage pigment patterns. Dots containing encapsulated metallic particulates enable omni-spectral electromagnetic wave and thermal radiation signature manipulation and control as well as cost-effective manufacturing. Single blended textile processed via needle punching produces hair/fur-like protrusions made from a multilayer fabric composition having EM wave and thermal radiation control elements. The protrusions subsequently contain EM propagation and thermal emission control elements on their surfaces for omni-spectral camouflage and detection mitigation. The systems expand the options for meeting the demands of today and future stealth missions.